Spiraea × brachybotrys Lange

A vigorous shrub, up to 8 ft high, branches gracefully arching; young wood downy, ribbed. Leaves oblong or ovate, 3⁄4 to 13⁄4 in. long, 1⁄3 to 3⁄4 in. wide, with a few teeth at the apex only; upper surface dull dark green, and slightly downy, lower one pale and felted with fine grey down. Flowers rosy pink, small, and crowded densely in stout panicles 11⁄2 to 3 in. long and about the same wide; they are borne at the end of leafy twigs, 3 to 12 in. long, that spring from the branches of the preceding year, expanding in June and July; flower-stalks and calyx hairy.

A hybrid between S. canescens and probably S. douglasii, inheriting much of the grace and vigour of the former. This is, indeed, one of the best of the taller summer-flowering kinds, the long shoots made one year branching copiously towards the top the following one, when each twig carries its terminal panicle, the whole forming a fine sheaf of delicately coloured blossom.

This hybrid is of unknown origin. It was described in 1882 from a plant grown under the name S. pruinosa, which is the name under which it was received at Kew around 1880 from the nurseryman Booth of Hamburg; it, or a similar clone, came to Kew around the same time from Lavallée as S. luxurians. Zabel considered that the plants under these two names were identical.

S. × fontenaysii Lebas S. × fontenaysiensis Dipp. – Similar to the preceding but with the leaves almost glabrous beneath. The flowers are white in the typical form, pink in ‘Rosea’. Raised by Billiard of Fontenay-aux-Roses before 1866, from S. canescens crossed with S. salicifolia.